Progestins, or combinations of progestins and estrogens, are used to inhibit ovulation, and to induce other physiological changes in the female reproductive system, and thereby to reduce the risk of pregnancy.
Various dosing regimens have been used to administer such hormones. These include for example, self-administration by oral delivery of a progestin and an estrogen for 21 days, followed by a 7 day “rest” interval, during which the woman typically experiences withdrawal (i.e., menstrual) bleeding. Other dosing regimens can also be used, including dosing regimens that involve longer durations of administration of a progestin and dosing regimens that involve use of low dose hormone during a non-treatment interval.
An important aspect of any effective contraceptive dosing regimen is that the regimen is convenient so as to facilitate compliance and that the doses delivered are effective to prevent or reduce the risk of pregnancy without exposing the woman to unnecessary risks of side effects. Side effects can include hormone-related adverse events and cycle control irregularities, particularly “breakthrough” bleeding.
A transdermal hormone delivery device for administering a progestin and an estrogen via a patch, and a skin permeation enhancer combination for use therein, are disclosed, e.g., in U.S. Pat. No. 7,045,145 and U.S. 20040054901, both of which are incorporated herein by reference as though fully set forth.